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Chinese Journal of Aeronautics 2020年第12期33卷 3073-3081页

作者： Jiakuan XU lei qiao Junqiang BAI School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China Department of Mathematics Imperial College LondonLondon SW72AZUnited Kingdom

Transition prediction is a hot research topic of fluid *** subsonic and transonic aerodynamic flows,e^(N) method based on Linear Stability Theory(LST)is usually adopted reliably to predict *** 2013,Coder and Maughmer established a transport equation for Tollmien-Schlichting(T-S)instability so that the e^(N) method can be applied to general Reynolds-Average-Navier-Stokes(RANS)solvers ***,this equation focuses on T-S instability,and is invalid for crossflow instability induced transition which plays a crucial role in flow instability of three-dimensional boundary ***,a transport equation for crossflow instability was developed in 2016,which is restricted to wing-like ***,in 2019,this model was extended to arbitrarily shaped geometries based on local ***,there are too many tedious functions and parameters in this version,and it can only be used for incompressible ***,in this paper,after a large amount of LST analyses and parameter optimization,an improved version for subsonic and transonic boundary layers is *** present improved model is more robust and more concise,and it can be applied widely in aeronautical flows,which has great engineering application value and *** extensive validation study for this improved transition model will be performed.

关键词： Boundary layer transition Crossflow instability Linear stability theory Transition Model Transonic flows

Picard Type Theorems Concerning Certain Small Functions

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Acta Mathematica Sinica,English Series 2017年第9期33卷 1275-1286页

作者： Pai YANG lei qiao College of Applied Mathematics Chengdu University of Information Technology School of of Mathematics and Information Science He'nan University of Economics and Law

Let f（z） be a meromorphic function in the complex plane, whose zeros have multiplicity at least k ＋ 1 （k 〉 2）. If sin z is a small function with respect to f（z）, then f（k）（z） - P（z） sin z has infinitely many zeros in the complex plane, where P（z） is a nonzero polynomial of deg（P（z）） ≠ 1. Keywords Meromorphic function, Nevanlinna theory, Picard type theorem.

关键词： Meromorphic function Nevanlinna theory Picard type theorem

Growth of certain harmonic functions in an n-dimensional cone

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Frontiers of Mathematics in China 2013年第4期8卷 891-905页

作者： lei qiao Guantie DENG Department of Mathematics and Information Science Henan University of Economics and Law Zhengzhou 450002 China School of Mathematical Science Beijing Normal University Laboratory of Mathematics and Complex Systems Ministry of Education Beijing 100875 China

We give the growth properties of harmonic functions at infinity in a cone, which generalize the results obtained by Siegel-Talvila.

关键词： Growth property harmonic function cone

Orientational Isomerism and Its Reactivity of a Main Group Sandwich Anion[Ge_(9)-In-Ge_(9)]^(5-)

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Chinese Journal of Chemistry 2023年第19期41卷 2432-2438页

作者： Hong-lei Xu lei qiao Zhong Ming Sun State Key Laboratory of Elemento-Organic Chemistry Tianjin Key Lab of Rare Earth Materials and ApplicationsSchool of Material Science and EngineeringNankai UniversityTianjin 300350China

Two isomers of a sandwich-type anion [Ge_(9)-In-Ge_(9)]^(5–) were synthesized by controlling the chelating agents (2,2,2-crypt/18-C-6). Further reactions with early/late transition metal complexes, Mo(CO)_(6) and Ni(COD)_(2), respectively, yielded two new types of inorganic sandwich derivatives: a half-sandwich cluster [Ge_(9)-In-Mo(CO)_(5)]^(3–) with a low-valence In(I) center and an unsymmetrical sandwich-type cluster {[(Ni@Ge_(9))In(Ni_(0.648)@Ge_(9))]}^(5–) due to the insertion of Ni atoms, respectively. The isolation of these new derivatives demonstrates the reactivity of sandwich-type [Ge_(9)-In-Ge_(9)]^(5–) acting as the precursor, which provides some enlightenment for constructing new inorganic sandwich compounds.

关键词： Sandwich complex Cluster compounds Main group elements Germanium Indium

Modular Verification of SPARCv8 Code

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Journal of Computer Science & Technology 2020年第6期35卷 1382-1405页

作者： Jun-Peng Zha Xin-Yu Feng lei qiao Department of Computer Science and Technology Nanjing UniversityNanjing 210023China State Key Laboratory for Novel Software Technology Nanjing UniversityNanjing 210023China Beijing Institute of Control Engineering Beijing 100080China

Inline assembly code is common in system software to interact with the underlying hardware platforms. The safety and correctness of the assembly code is crucial to guarantee the safety of the whole system. In this paper, we propose a practical Hoare-style program logic for verifying SPARC (Scalable Processor Architecture) assembly code. The logic supports modular reasoning about the main features of SPARCv8 ISA (instruction set architecture), including delayed control transfers, delayed writes to special registers, and register windows. It also supports relational reasoning for refinement verification. We have applied it to verify that there is a contextual refinement between a context switch routine in SPARCv8 and a switch primitive. The program logic and its soundness proof have been mechanized in Coq.

关键词： Scalable Processor Architecture Version 8(SPARCv8) assembly code verification context switch Coq refinement verification

Transition study of 3D aerodynamic configures using improved transport equations modeling

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Chinese Journal of Aeronautics 2016年第4期29卷 874-881页

作者： Xu Jiakuan Bai Junqiang Zhang Yang qiao lei School of Aeronautics Northwestern Polytechnical University

As boundary layer transition plays an important role in aerodynamic drag prediction, the proposal and study of transition prediction methods simulating the complex flow phenomena are prerequisite for aerodynamic design. In this paper, with the application of the linear stability theory based on amplification factor transport transition equations on the two-equation shear stress transport (SST) eddy-viscosity model, a new method, the SST-NTS-NCF model, is yielded. The new amplification factor transport equation for the crossflow instability induced transition is proposed to add to the NTS equation proposed by Coder, which simulates Tollmien-Schlichting wave transition. The turbulent kinetic energy equation is modified by introducing a new source term that simulates the transition process without the intermittency factor equation. Finally, coupled with these two amplification factor transport equations and SST turbulence model, a four-equation transition turbulence model is built. Comparisons between predictions using the new model and wind-tunnel experiments of NACA64(2) A015, NLF(2)-0415 and ONERA-D infinite swept wing and ONERAM6 swept wing validate the predictive quality of the new SST-NTS-NCF model. (C) 2016 Chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd.

关键词： Boundary layer CFD Crossflow instability Linear stability theory Transition Turbulence

An efficient schedulability analysis based on worst-case interference time for real-time systems

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Science China(Information Sciences) 2024年第9期67卷 88-104页

作者： Hongbiao LIU Mengfei YANG lei qiao Xi CHEN Jian GONG School of Computer Science and Technology Xidian University China Academy of Space Technology Beijing Institute of Control Engineering

Real-time systems are widely implemented in the Internet of Things(IoT) and safety-critical systems, both of which have generated enormous social value. Aiming at the classic schedulability analysis problem in real-time systems, we proposed an exact Boolean analysis based on interference(EBAI) for schedulability analysis in real-time systems. EBAI is based on worst-case interference time(WCIT), which considers both the release jitter and blocking time of the task. We improved the efficiency of the three existing tests and provided a comprehensive summary of related research results in the field. Abundant experiments were conducted to compare EBAI with other related results. Our evaluation showed that in certain cases, the runtime gain achieved using our analysis method may exceed 73% compared to the stateof-the-art schedulability test. Furthermore, the benefits obtained from our tests grew with the number of tasks, reaching a level suitable for practical application. EBAI is oriented to the five-tuple real-time task model with stronger expression ability and possesses a low runtime overhead. These characteristics make it applicable in various real-time systems such as spacecraft, autonomous vehicles, industrial robots, and traffic command systems.

关键词： five-tuple real-time task model real-time system spacecraft Internet of Things exact schedulability analysis worst-case interference time

[Cd(Sn_(9))_(2)]^(6-) and[Cd(Ni@Sn_(9))_(2)]^(6-):Reactivity and coordination chemistry of empty and Ni-centered[Sn_(9)]^(4-) Zintl ions

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Chinese Chemical Letters 2023年第1期34卷 523-526页

作者： Ya-Nan Yang lei qiao Zhong-Ming Sun State Key Laboratory of Elemento-Organic Chemistry Tianjin Key Lab of Rare Earth Materials and ApplicationsSchool of Material Science and EngineeringNankai UniversityTianjin 300350China

To investigate the reactivity of homoatomic clusters[E_(9)]^(4-)(E=Si-Pb)and intermetalloid clusters[M@E_(9)]^(q-),the reactions of the Zintl anions[Sn_(9)]^(4-) and[Ni@Sn_(9)]^(4-) with the CdMes_(2)(Mes=Mesitylene)in the presence of 2.2.2-crypt were carried *** new compounds[K(2.2.2-crypt)]_(6)[(Sn_(9))Cd(Sn_(9))]·en(1)and[K(2.2.2-crypt)]_(6)[(Ni@Sn_(9))Cd(Ni@Sn_(9))]·en(2)were *** 1 and 2 were characterized by single-crystal X-ray diffraction,energy dispersive X-ray(EDX),and electrospray ionization mass spectrometry(ESI-MS),and can be viewed as two[Sn_(9)]^(4-)or[Ni@Sn_(9)]^(4-)subunits bridged by Cd ion in an η^(3):η^(3) coordination *** chemical calculations reveal the relationships between the geometries and electronic structures of clusters 2a,[Ni_(3)Ge_(18)]^(4-)and[Cu_(4)@Sn_(18)]^(4-).Further electron localization technique(Ad NDP method)was performed to explain chemical bonding patterns of 1a.

关键词： Heterometallic complexes Sn cluster Zintl anions DFT calculation Electronic structure

Vascular macrophages sense octanal and drive athero-inflammation

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Cellular & Molecular Immunology 2022年第10期19卷 1077-1078页

作者： lei qiao Meng Zhang Cheng Zhang The Key Laboratory of Cardiovascular Remodeling and Function Research Chinese Ministry of EducationChinese National Health Commission and Chinese Academy of Medical SciencesThe State and Shandong Province Joint Key Laboratory of Translational Cardiovascular MedicineDepartment of CardiologyQilu HospitalCheeloo College of MedicineShandong UniversityJinanChina Cardiovascular Disease Research Center of Shandong First Medical University Central Hospital Affiliated to Shandong First Medical UniversityJinanChina

In a recent paper in Science,Orecchioni et *** the expression of olfactory receptor 2(OLFR2)and its human ortholog olfactory receptor 6A2(OR6A2)in vascular macrophages,which detects the compound octanal and activates the NLRP3 inflammasome,driving vascular inflammation and atherosclerosis progression[1].Their work provides new insights into the pathogenesis of atherosclerosis and suggests that inhibiting OR6A2 may represent a promising anti-inflammatory strategy to preventand treatat herosclerosis(Fig.1).

关键词： NLRP3 inflammation

Dynamics of a multiplex neural network with delayed couplings

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Applied Mathematics and Mechanics(English Edition) 2021年第3期42卷 441-456页

作者： Xiaochen MAO Xingyong LI Weijie DING Song WANG Xiangyu ZHOU lei qiao Department of Engineering Mechanics College of Mechanics and MaterialsHohai UniversityNanjing 211100China

Multiplex networks have drawn much attention since they have been observed in many systems,e.g.,brain,transport,and social *** this paper,the nonlinear dynamics of a multiplex network with three neural groups and delayed interactions is *** stability and bifurcation of the network equilibrium are discussed,and interesting neural activities of the network are *** on the neuron circuit,transfer function circuit,and time delay circuit,a circuit platform of the network is *** is shown that delayed couplings play crucial roles in the network dynamics,e.g.,the enhancement and suppression of the stability,the patterns of the synchronization between networks,and the generation of complicated attractors and multi-stability coexistence.

关键词： neural network time delay synchronization coexisting attractor